The invention concerns a tubular intramedullary nail to be used in orthopedics for the reduction of bone fractures.
It is well known that in orthopedic surgery tubular metal rods called "nails" to be inserted in the fractured bone after drilling the medullary canal of the bone itself are used in most cases for the treatment of fractures, especially fractures of the long bones. In order to avoid the rotation of the fragments and their shortening in multifragmented fractures. The known technique requires the intersection of said nail by means of anchoring screws that pass through apposite holes. The insertion of the nail and, above all, the distal locking of the nail itself on the fragments of the fractured bone are rather complex operations, due also to the fact that it is often difficult to center the screws to be inserted on the nail holes.
Another drawback connected with the known technique is represented by the fact that during the fracture consolidation time, the nail, locked as it is through transverse screws, actually prevents any relative movement of the fractured bone fragments in the longitudinal direction. This is obviously a limitation of the known technique, in fact, since a moderate physiological absorption of the fractured parts takes usually place, a dynamic compaction is practically impossible. Therefore, the impossibility to bring the two bone fragments under dynamic load near each other prolongates the fracture consolidation time.
The U.S. Pat. No. 5,057,103 discloses a nail for long bones comprising a tubular body having in his interior an anchoring device which holds the lower part of the fractured bone permitting the compression of the parts of the fractured bone, but said kind of nail, per se, does not avoid the rotation and the shearing of said fractured parts.